package string;

/**
 * Compare two version numbers version1 and version2.
 * If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0.
 * You may assume that the version strings are non-empty and contain only digits and the . character.
 * The . character does not represent a decimal point and is used to separate number sequences.
 * For instance, 2.5 is not "two and a half" or "half way to version three", 
 * it is the fifth second-level revision of the second first-level revision.
 * Here is an example of version numbers ordering:
 * 0.1 < 1.1 < 1.2 < 13.37
 *
 */
public class CompareVersionNumbers {

	public int compareVersion(String version1, String version2) {
        String[] parts1 = version1.split("\\.");    
        String[] parts2 = version2.split("\\.");
          
        for (int i = 0; i < Math.max(parts1.length, parts2.length); i++) {
            int subVersion1 = i < parts1.length ? Integer.parseInt(parts1[i]) : 0;
            int subVersion2 = i < parts2.length ? Integer.parseInt(parts2[i]) : 0;
            if (subVersion1 < subVersion2) return -1;
            if (subVersion1 > subVersion2) return 1;
        }
        
        return 0;    
    }

}
